What do I do if I am being sued by my previous landlord?

I left my apartment because they never fixed anything, there was a mold build up in the bathroom and they painted but it was still coming back. I have allergies this year which I never had before and my cousin who has a mild case of asthma had breathing problems. The landlord said that he had the city inspect it and there is no mold problem and he will forward a copy of the report to my lawyer. I left a month before and did not pay that months rent. Should I just pay it to avoid a legal process since I might be liable for their attorney fees?
Well I have pictures of the mold and I told them that in the letter I sent them stating that I have proof and I am breaking the lease due to failure to maintain the premises and that the mold is a threat to my health.